Because he is significantly exaggerating the detriment Worster is.
As
@ECisGod pointed out, when we play poorly, there are a lot of things that go poorly that have nothing to do with him. There was a video posted of all the threes that Iowa made. Only one of them involved Worster being the guy late to rotate, and that was only because he was guarding one guy on the wing, a pass was made towards the top of the the key and Worster was the guy who had to try to run and guard that guy too.
We kind of play a high-risk, high-reward defense. When teams aren't great outside shooters or have an off night, it looks fantastic. When they are hitting, we are in trouble because they get open looks.